# wcstoimax, wcstoumax

From cppreference.com
< c‎ | string‎ | wide

Defined in header ``<inttypes.h>`` |  |
intmax_t wcstoimax( const wchar_t *restrict nptr, wchar_t **restrict endptr, int base ); |  | (since C99)
uintmax_t wcstoumax( const wchar_t *restrict nptr, wchar_t **restrict endptr, int base ); |  | (since C99)

Interprets an unsigned integer value in a wide string pointed to by `nptr`.

Discards any whitespace characters (as identified by calling `iswspace`) until the first non-whitespace character is found, then takes as many characters as possible to form a valid base-n (where n=`base`) unsigned integer number representation and converts them to an integer value. The valid unsigned integer value consists of the following parts:

- (optional) plus or minus sign
- (optional) prefix (`0`) indicating octal base (applies only when the base is 8 or ​0​)
- (optional) prefix (`0x` or `0X`) indicating hexadecimal base (applies only when the base is 16 or ​0​)
- a sequence of digits

The set of valid values for base is `{0, 2, 3, ..., 36}`. The set of valid digits for base-`2` integers is `{0, 1}`, for base-`3` integers is `{0, 1, 2}`, and so on. For bases larger than `10`, valid digits include alphabetic characters, starting from `Aa` for base-`11` integer, to `Zz` for base-`36` integer. The case of the characters is ignored.

Additional numeric formats may be accepted by the currently installed C locale.

If the value of `base` is ​0​, the numeric base is auto-detected: if the prefix is `0`, the base is octal, if the prefix is `0x` or `0X`, the base is hexadecimal, otherwise the base is decimal.

If the minus sign was part of the input sequence, the numeric value calculated from the sequence of digits is negated as if by unary minus in the result type, which applies unsigned integer wraparound rules.

The functions sets the pointer pointed to by `endptr` to point to the wide character past the last character interpreted. If `endptr` is a null pointer, it is ignored.

### Parameters

nptr | - | pointer to the null-terminated wide string to be interpreted
endptr | - | pointer to a pointer to a wide character.
base | - | base of the interpreted integer value

### Return value

Integer value corresponding to the contents of `str` on success. If the converted value falls out of range of corresponding return type, range error occurs and INTMAX_MAX, INTMAX_MIN, UINTMAX_MAX, or ​0​ is returned, as appropriate. If no conversion can be performed, ​0​ is returned.

### Example

Run this code

    #include <errno.h>
    #include <inttypes.h>
    #include <stdio.h>
    #include <string.h>
    #include <wchar.h>

    int main(void)
    {
      wchar_t* endptr;

      wprintf(L"%ld\n", wcstoimax(L" -123junk", &endptr, 10)); /* base 10                    */
      wprintf(L"%ld\n", wcstoimax(L"11111111", &endptr, 2));   /* base 2                     */
      wprintf(L"%ld\n", wcstoimax(L"XyZ", &endptr, 36));       /* base 36                    */
      wprintf(L"%ld\n", wcstoimax(L"010", &endptr, 0));        /* octal auto-detection       */
      wprintf(L"%ld\n", wcstoimax(L"10", &endptr, 0));         /* decimal auto-detection     */
      wprintf(L"%ld\n", wcstoimax(L"0x10", &endptr, 0));       /* hexadecimal auto-detection */

      /* range error             */
      /* LONG_MAX+1 --> LONG_MAX */
      errno = 0;
      wprintf(L"%ld\n", wcstoimax(L"9223372036854775808", &endptr, 10));
      wprintf(L"%s\n", strerror(errno));
    }

Output:

    -123
    255
    44027
    8
    10
    16
    9223372036854775807
    Numerical result out of range

### References

- C11 standard (ISO/IEC 9899:2011):

  - 7.8.2.4 The wcstoimax and wcstoumax functions (p: 220)

- C99 standard (ISO/IEC 9899:1999):

  - 7.8.2.4 The wcstoimax and wcstoumax functions (p: 201)

### See also

strtoimaxstrtoumax (C99)(C99) | converts a byte string to intmax_t or uintmax_t (function)
wcstolwcstoll (C95)(C99) | converts a wide string to an integer value (function)
wcstoulwcstoull (C95)(C99) | converts a wide string to an unsigned integer value (function)
C++ documentation for wcstoimax, wcstoumax

Retrieved from "https://en.cppreference.com/mwiki/index.php?title=c/string/wide/wcstoimax&oldid=133860"